Polyurethane foams constitute highly problematic waste due to their low density and consequently large volume. Among the most promising recycling approaches, the glycolysis of polyurethane waste stands out and was extensively discussed in this article. Existing literature reviews lack a detailed analysis of glycolysis processes and a clear presentation of the most important data. However, in this review, the scientific literature on glycolysis has been thoroughly examined and updated with the latest research in the field. The article provides an overview of glycolysis methods, categorized into rigid and flexible foams, along with a review of the catalysts and process conditions employed. Additionally, this study offers a comprehensive analysis of industrial methods protected by active patents, which has not been previously explored in the literature. This detailed examination of patent information adds significant value to the review and distinguishes it from others. Furthermore, this review also aims to introduce the main types of polyurethanes and their properties. It outlines the fundamentals of recycling strategies, thermomodernization trends, and environmental considerations, highlighting the critical role of recycling in the industry. The article serves as a complete foundation for exploring new alternative methods in this field.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11433504 | PMC |
| http://dx.doi.org/10.3390/ma17184617 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Shear thickening inside elastic open-cell foams under dynamic compression.
Soft Matter
January 2025
James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637, USA.
We measure the response of open-cell polyurethane foams filled with a dense suspension of fumed silica particles in polyethylene glycol at compression speeds spanning several orders of magnitude. The gradual compressive stress increase of the composite material indicates the existence of shear rate gradients in the interstitial suspension caused by wide distributions in pore sizes in the disordered foam network. The energy dissipated during compression scales with an effective internal shear rate, allowing for the collapse of three data sets for different pore-size foams.
View Article and Find Full Text PDFThe Complex Valorization of Black Alder Bark Biomass in Compositions of Rigid Polyurethane Foam.
Materials (Basel)
December 2024
Latvian State Institute of Wood Chemistry, Dzerbenes Street 27, LV-1006 Riga, Latvia.
The use of black alder (BA) bark biomass in rigid polyurethane (PUR) foam compositions was the main task of investigation. Extractive compounds isolated from the bark through hot water extraction were used as precursors for bio-polyol synthesis via acid-free liquefaction with the polyether polyol Lupranol 3300 and through oxypropylation with propylene carbonate. The OH functionality and composition of the polyols were analyzed via wet chemistry and FTIR spectroscopy.
View Article and Find Full Text PDFThe Catalytic Degradation of Waste PU and the Preparation of Recycled Materials.
Polymers (Basel)
December 2024
School of Energy and Building Environment, Guilin University of Aerospace Technology, Guilin 541004, China.
In this paper, we investigated the efficient metal-free phosphorus-nitrogen (PN) catalyst and used the PN catalyst to degrade waste PU with two-component binary mixed alcohols as the alcohol solvent. We examined the effects of reaction temperature, time, and other factors on the hydroxyl value and viscosity of the degradation products; focused on the changing rules of the hydroxyl value, viscosity, and molecular weight of polyols recovered from degradation products with different dosages of the metal-free PN catalyst; and determined the optimal experimental conditions of reaction temperature 180 °C, reaction time 3 h, and PN dosage 0.08%.
View Article and Find Full Text PDFα-Tocopherol and Trolox as Effective Natural Additives for Polyurethane Foams: A DFT and Experimental Study.
Molecules
December 2024
Institute of Chemistry, University of Miskolc, 3515 Miskolc-Egyetemváros, Hungary.
In this work, α-tocopherol and trolox were studied as compounds that have high biological activity. α-Tocopherol is considered a food additive because the refining process of vegetable oils causes the depletion of this vitamin, and thus, its inclusion is required to keep them from oxidizing. Computational tools have determined the antioxidant activity of these additives.
View Article and Find Full Text PDFEffect of Chemical Structure and Apparent Density of Rigid Polyurethane Foams on the Properties of Their Chemical Recycling Products.
Materials (Basel)
December 2024
Faculty of Chemical Engineering and Technology, Cracow University of Technology, Warszawska 24, 31-155 Kraków, Poland.
The aim of this work was to synthesize polyurethane foams based on petrochemical polyols and biopolyols with specific apparent densities (40, 60, 80, 100, and 120 kg/m), test their properties, glycolyze them, and finally analyze each glycolyzed product. The petroleum-based foams, used as reference foams, and the bio-based foams underwent a series of standard tests to define their properties (the content of closed cells 20-95%, compressive strength 73-1323 kPa, thermal conductivity 24-42 mW/m∙K, brittleness 4.6-82.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!